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Discussion Starter · #1 · (Edited)
*note: This post covers the accelerator position sensor (APS) not the throttle position sensor (TPS).

Here's a brief tutorial on my method of adjusting the APS (accelerator position sensor) on a Kia Forte.

Step 1: Gather your tools

A. Multimeter (set to DC voltage- 20 scale)
B. A pin or needle (mine have alligator clips attached to them)
C. A small phillips screwdriver



Step 2: With the engine off, locate and remove the connector from the top of the APS sensor (attached to the left side of the throttle pedal)




Step 3: Insert pin or needle into the third wire from the left (orange). When inserting, make sure that you stick the needle where the wire comes into the connector (the side with the yellow retainer)- not the side that plugs into the APS sensor. This is called back-probing.





Step 4: Plug the connector back into the APS and connect the multimeter (positive to needle on APS plug and negative to a good ground).



Step 5: Start the engine. Your multimeter should read ~ 0.78 volts (that's what mine was). If your multimeter is reading 0 volts, check your connections- you may not have a good connection with the wire inside the connector.

Step 6: Loosen the 5 screws circled in red, but don't remove the sensor ( I borrowed this pic from the original tutorial).



Step 7: While watching the multimeter, rotate the APS until you read close to, but no more than 1.0 volts. Mine started out at 0.98 volts, but decreased to 0.94 volts as I re-tightened the screws (I feel that 0.95 volts is ideal, but 0.94 volts is close enough for me). It may also take some wiggling/ more loosening of the screws to get the voltage to change.



Step 8: Re-tighten the 5 APS screws, holding the sensor in its new position as you tighten (voltage will drop some).

Step 9: Remove the needle from the connector.

Step 10: Put your tools away! It's time to enjoy your work! :)
 

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damn nice clear and concise write up---thanks!
(its still on my list of things to do-but this makes it so much safer looking :)
 

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2021 Forte GT w/GT2, Currant Red, SXTH Element Intercooler Kit, Evilla Exhaust, Takeda S2 Intake
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Here's a brief tutorial on my method of adjusting the TPS (throttle position sensor) on a Kia Forte.


Step 6: Loosen the 5 screws circled in red, but don't remove the sensor ( I borrowed this pic from the original tutorial).



Step 7: While watching the multimeter, rotate the TPS until you read close to, but no more than 1.0 volts. Mine started out at 0.98 volts, but decreased to 0.94 volts as I re-tightened the screws (I feel that 0.95 volts is ideal, but 0.94 volts is close enough for me). It may also take some wiggling/ more loosening of the screws to get the voltage to change.



Step 8: Re-tighten the 5 TPS screws, holding the sensor in its new position as you tighten (voltage will drop some).

:)
:)Great write-up for the masses!

Step 6: Like to point out that the fifth (upper right) screw is a set screw -- may have to remove it or loosen it quite a bit to allow for adjustment. The other four screws just need to be loosened a bit.

Step 7: 0.94 volts is really the most you want at idle. It will get rid of the "dead spot" completely -- having it a 1.0 and up volts can cause erratic idling.
 

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I did mine and got it down to .98v seems like the sweet spot. Will do more testing over the next week or so to see how it behaves.

BTW: I did it on the SX version 2.4l
 

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I wanta do this mod but I don't happen to have a multimeter handy. Any other easy method?
 

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Discussion Starter · #10 ·
I recommend purchasing a cheap one just for this project. You can get them at most hardware stores. Heck, I think some dollar stores even carry them.
 

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Oh mannnnn, this has to be the best thing ever, well not the best but its up there. Thanks for the DIY. was extremely easy. Got it set at .94v Threw a couple codes, but not a biggie. Went to work and used the GDS (kia scan tool) and found codes P2122 (Throttle/Pedal Position Sensor/Switch "D" Circuit Low Input) A P2127 (Throttle/Pedal Position Sensor/Switch "E" Circuit Low Input) and a P2104 (Throttle Actuator Control System - Forced Idle ) Just cleared the codes. took it for a rip and rescanned the PCM and found no codes. MINT
 

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Discussion Starter · #13 ·
Glad this makes things easier ( I'm a high school teacher, btw..lol). CK, when adjusting the sensor, did you drop below .7 volts?
 

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New user been reading this site for a while.

Just wanted to say thank you for the write up, night and day difference. I set mine to .9 volts.

And for those asking yes this works on the auto's, now it actually feels like a manual shift into second using manual mode :) And as someone else said which I will back the effect its like driving a new car.

I just wish I would have known about this before I would have gotten the manual over the auto but its all good..

Thank you again!
 

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CK, when adjusting the sensor, did you drop below .7 volts?
Probably. I didnt know which way to move the sensor at first so more than likely ya. no biggie. its all good.
 

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"Step 4: Plug the connector back into the TPS and connect the multimeter (positive to needle on TPS plug and negative to a good ground). "

sorry for my ingorance...what would be a good ground?? i never used a voltimeter before...so im a litle confused :S

BTW: does anybody checked if with this mod, with cold engine at the start the revs will go further than usual? and by using the A/C ???
 

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on the sedan sx's there is a bolt in the floor kinda right between the brake and gas pedals. you should see a couple of wires bolted to the floor. that would be a good ground.
 

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I did this and my idle rpm starts at 2 then drops to 1. Before i did this it was 1.5 to start then it would go to .5. Is this a problem?
 

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Discussion Starter · #19 · (Edited)
Lb
I did this and my idle rpm starts at 2 then drops
to 1. Before i did this it was 1.5 to start then it would go to .5. Is this a problem?

Sounds like you moved your TPS too much. Follow the guidelines in the tutorial. I'll bet your voltage is over 1.0 volts. Don't worry. It's an easy fix. :)
 

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Lb


Sounds like you moved your TPS too much. Follow the guidelines in the tutorial. I'll bet your voltage is over 1.9 volts. Don't worry. It's an easy fix. :)
Also i could not remove the "thing" that is connected to the accelerator so it was very hard for me to get a read on the voltage so i just loosend all the screws and tightend the bottom left screw and push it as close as i could to the front of the car. Then i tightend all of these. I did not have a small phillips so i had to use a drill bit phillips and a wrench hah
 
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